Nonlinear Model Predictive Control for Automatic Berthing of the Underactuated Twin-propeller Twin-Rudder Ship

In order to cope with the problem that the automatic berthing control of the underactuated ship cannot track any path, this paper proposes an automatic berthing method for underactuated twin-propeller twin-rudder ships based on the nonlinear model predictive control. Through establishing the ship berthing maneuvering constrained optimization model, the time sequences of the control commands are obtained based on the rolling optimization feature of the model predictive control. Through numerical simulation of forward berthing and U-turn berthing, which are the two typical berthing methods, the effectiveness and adaptability of the proposed control method are verified. The research results can provide references for the berthing control design of the underactuated ship.